The optimal strategy for pertussis vaccination: a systematic review and meta-analysis of randomized control trials and real-world data

Objective: Severe pertussis infection has been reported in infants before receiving routine immunization series. This problem could be solved by vaccinating mothers during pregnancy or children at birth. This study aimed to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) and real-world evidence to evaluate the optimal strategy for pertussis vaccination. Data Sources: PubMed, Embase, and the Cochrane Library databases were searched until December 2020. Study Eligibility Criteria: RCTs, cohort studies, case-control studies, and case series were included if they investigated the efficacy, immunogenicity, and safety of acellular pertussis vaccine during pregnancy and at birth. Methods: Number of pertussis cases, severe adverse events (SAEs), and pertussis antibody concentration in infants before and after they receive routine vaccination series were extracted and random-effect model was used to pool the analyses. Results: Overall, 29 studies were included. Our meta-analysis revealed that pertussis immunization during pregnancy significantly increased the concentrations of 3 pertussis antibodies and reduced the incidence rates of infected infants below 3 months of age (odds ratio, 0.22; 95% confidence interval, 0.14–0.33). Similarly, infants vaccinated at birth had higher levels of pertussis antibody than those who were not. No significant difference in rates of severe adverse events was seen in all vaccination groups (during pregnancy [risk ratio, 1.18; 95% confidence interval, 0.76–1.82] and at birth [risk ratio, 0.72; 95% confidence interval, 0.34–1.54]). Conclusion: Pertussis vaccination during pregnancy could protect infants against pertussis disease before the routine vaccination. Pertussis immunization at birth would be an alternative for infants whose mothers did not receive pertussis vaccines during pregnancy.